Bottom Line:
Chimeric rate and survival rate after cell transplantation was evaluated.Expressions of human hepatic-related genes were detected.A human albumin enzyme-linked immunosorbent assay was performed after 50 days of transplantation.

Introduction: Chimeric mice with humanized livers were recently established by transplanting human hepatocytes. This mouse model that is repopulated with functional human hepatocytes could be a useful tool for investigating human hepatic cell biology and drug metabolism and for other preclinical applications. Successfully transplanting human hepatocytes into mice requires that recipient mice with liver failure do not reject these human cells and provide a suitable microenvironment (supportive niche) to promote human donor cell expansion and differentiation. To overcome the limitations of current mouse models, we used Alb-TRECK/SCID mice for in vivo human immature hepatocyte differentiation and humanized liver generation.

Methods: 1.5 μg/kg diphtheria toxin was administrated into 8-week-old Alb-TRECK/SCID mice, and the degree of liver damage was assessed by serum aspartate aminotransferase activity levels. Forty-eight hours later, mice livers were sampled for histological analyses, and the human donor cells were then transplanted into mice livers on the same day. Chimeric rate and survival rate after cell transplantation was evaluated. Expressions of human hepatic-related genes were detected. A human albumin enzyme-linked immunosorbent assay was performed after 50 days of transplantation. On day 60 after transplantation, drug metabolism was examined in mice.

Conclusion: Our model of a humanized liver in Alb-TRECK/SCID mice may provide for functional applications such as drug metabolism, drug to drug interactions, and promote other in vivo and in vitro studies.

Mentions:
We also evaluated human drug metabolism-related gene expression by quantitative PCR and microarray analysis to assess whether human primary FLC- and HpSC-derived humanized livers could be used for human drug metabolism studies. At 8 weeks after transplantation, we observed very high gene expression levels associated with the human hepatic functional markers ALB, AFP, and cytochrome P450, including CYP3A4, 2C9, and 2C19, which collectively metabolize over 80% of clinical drugs (Figure 5A). Almost none of the probes on the human gene expression array had cross-hybridized with murine mRNA.Figure 5

Mentions:
We also evaluated human drug metabolism-related gene expression by quantitative PCR and microarray analysis to assess whether human primary FLC- and HpSC-derived humanized livers could be used for human drug metabolism studies. At 8 weeks after transplantation, we observed very high gene expression levels associated with the human hepatic functional markers ALB, AFP, and cytochrome P450, including CYP3A4, 2C9, and 2C19, which collectively metabolize over 80% of clinical drugs (Figure 5A). Almost none of the probes on the human gene expression array had cross-hybridized with murine mRNA.Figure 5

Bottom Line:
Chimeric rate and survival rate after cell transplantation was evaluated.Expressions of human hepatic-related genes were detected.A human albumin enzyme-linked immunosorbent assay was performed after 50 days of transplantation.

Introduction: Chimeric mice with humanized livers were recently established by transplanting human hepatocytes. This mouse model that is repopulated with functional human hepatocytes could be a useful tool for investigating human hepatic cell biology and drug metabolism and for other preclinical applications. Successfully transplanting human hepatocytes into mice requires that recipient mice with liver failure do not reject these human cells and provide a suitable microenvironment (supportive niche) to promote human donor cell expansion and differentiation. To overcome the limitations of current mouse models, we used Alb-TRECK/SCID mice for in vivo human immature hepatocyte differentiation and humanized liver generation.

Methods: 1.5 μg/kg diphtheria toxin was administrated into 8-week-old Alb-TRECK/SCID mice, and the degree of liver damage was assessed by serum aspartate aminotransferase activity levels. Forty-eight hours later, mice livers were sampled for histological analyses, and the human donor cells were then transplanted into mice livers on the same day. Chimeric rate and survival rate after cell transplantation was evaluated. Expressions of human hepatic-related genes were detected. A human albumin enzyme-linked immunosorbent assay was performed after 50 days of transplantation. On day 60 after transplantation, drug metabolism was examined in mice.

Conclusion: Our model of a humanized liver in Alb-TRECK/SCID mice may provide for functional applications such as drug metabolism, drug to drug interactions, and promote other in vivo and in vitro studies.